Type-writing machine.



A. S. DENNIS.

TYPE WRITING MACHINE.

APPLIOAJTION FILED DBO. a. 1909.

1991,706 Patented May 9, 1911.

UNITE s'rarns "flan 'r r on.

ADOLPHU'S S. DENIQ'IS, OF LAKEWOOD, OHIO, ASSIGNOR. '10 UNDER'W'OOD TYPEWRI'I'ER COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

TYPE-WRITING MACHINE.

Specification of Letters Patent.

Patented May 9, 1911.

Application filed December 8, 1909. Serial No. 531,921,

To all whom it may concern:

Be it known that I, ADOLPHUS S. DENNIS, a citizen of the United States residing in Lakewood, in the county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Type-IVrit-ing Machines, of which the following is a specification. v

This invention relates to the pressure rolls, which run upon the cylindrical platens of typewriting machines, for feeding the paper around the platen.

In many machines now-in use it is found difficult to introduce a thick card or en-- velop or'a quantity of sheets of substantial thickness, and this difficult is due to the fact that the leading edge 0 the card or the pack of sheets separates the pressure roll from the platen. The pressure roll bein thus separated from the platen lies dca and has little or no tendency to advance the card or the like. The same is true with relation to the forward pressure roll. Moreover'the latter is often found'not to have suflici'enttendency to advance the card or pack of sheets after its bottom edge has passed the first pressure roll.

The principal object of this invention is to overcome these dilliculties, and to provide a simple and inexpensive devlce that may be readily applied to existing machines, for effecting a substantial improvement in the carrying capacity of the pressure rolls. To this end I first connect the pressure rolls to each other in such a manner that when the forward, roll rotates the rear roll must rotate also; and vice versa. TllllS when a pack of sheets is being introduced between the platen and the first pressure roll, the latter,

although separated from the platen, does not lie lifeless, but iscauscd to rotate when the platen rotates, by reason of the gear or other driving connection between such pressure roll and the forward pressure roll, which at this time 1s running in direct contact with the platen, and hence is rotated thereby. Moreover after the card or pack of sheets has passed the first pressure roll 1 and is fed only by the forward pressure roll, the latter is positively rotated by means of its gear connection to the first (or rear) pressure roll, which at this time is running in direct contact with the platen, and is hence driven thereby. In short the gearing enables one pressure roll to drive the other, and this construction is of great advantage when one roll is running upon the platen, and the other roll is hearing the entire burden of feeding the sheets.

The gear cbnnection between the forward and rear pressure rolls comprises pinions for the pressure rolls, and an idle gear with. which both pinions mesh, said idle gear being preferably mounted upon the axle of I the platen itself, and of a diameter approximating that of the platen. Said idle gear is preferably not fixed to the platen, but connected thereto in a manner to enable independent rotation of the idle gear and the platen relatively to each other. To further improve the construction a' friction device is employed between the platen and said idle gear, for the purpose of enabling the platen, acting as .a driver, to aid (through the train of gearing) in rotating both front and rear pressure rolls; although this friction device will also be useful in machines in which either more or less than two rolls arefemploycd. The frictional connection between the platen and the gear is sufficient to aid substantially in driving the pressure rolls, so that itis notnecessary to depend, as is usually the case, upon the surface friction between the platen and the paper, and also upon the surface friction between the paper and the pressure rolls, for rotating the latter. This friction, while suflicient to aid in the operation of the pressurerolls, is not sufiicient to enable the platen to positively insure the rotation of said rolls. Hence the frictional connection can be made of such strength as to be of a decided advantage without any resulting disadvantage.

is made in twoparts, one carrying the rolls and the other jointed by a, universal joint to the main portion of the roll shaft and by another universal joint to the pinion, so that thelatter is positively connected to the roll,-

irrespective to the position of the roll; ==Ihi ls universal joint also accommodates the releasing movement of the rolls from the plateng p formed in several semen One effect of wrapping a thick pack of sheets around the platen is to increasethe diameter of the rotating mass, without increasing the diameter of the pressure rolls which. are geared together and frictionally connected to said platen. To avoid any consequent tendency of the rolls to retard the outer sheet of the pack, said pressure rolls are made slightly over size. Or in other words, the construction is such that the rolls tend to rotate at a higher surface speed than the platen when the rolls are directly in contact therewith. The same result may of course be attained by suitably proportioning the idle gear to the pinions, instead of changing the diameter of the rolls. From this it follows that when the diameter of the rotating mass is enlarged by wrapping a thick pack of sheets around the platen, the surface speed of the pressure rolls will be equal or approximately equal to the surface speed of the rotating mass, and hence there will be no tendency to retard the outer sheet thereof. At the same time, the fact that the rollstend to rotate faster than the platen when only a single sheet of paper is being fed, is somewhat of an advantage, because it tends to insure that the sheet shall move positively with the platen; the frictional connection between the platen and the gearing not being strong enough to cause the sheet to be advanced faster than the platen.

In the accompanying drawings, Figure 1 is a perspective view of the platen and pres sure rolls inverted, showing particularly the flexible connection between the pressure roll shafts and their pinions, andalso showing the connection of the idle gear to the platen. Fig. 2 is a rear sectional elevation showing one end of the platen and parts'adjacent thereto. Fig. 3 is an end elevation showing the relation of the idle gear, the pinions and the pressure rolls. Fig. 4: is a diagram to illustrate the differences between the pitch diameters of the pinions and the diameters of the rolls connected thereto. Fig. 5 is a plan of the pressure roll system. inverted. Fig. 6 is a diagram to illustrate the manner in which a pack of sheets is carried around the platen.

lnthe Underwood typewriting machine, which is illustrated in the drawings, types 1 strike rearwardly against the front side of a cylindrical platen 2, which by means of an axle 3 is journaled in the ends 4 of a platen frame. Running upon the platen is a rear or introductory pressure roll 5 usually to a common shaft 6 to rotate therewith. A front pressure roll 7 is similarly constructed and mounted upon the shaft 8. The shafts are pressed toward the platen by arms 9, actuated by springs 10. Releasing mechanism of usual conupon or connected sections which are fixed struction includes a. release key 1 1 mounted upon the platen frame and a link 12 con necting said key to a rock shaft 13, t-l1e'lat-- ter having flats or cams, as usual, to act 5 upon the roll-carrying arms, to fore? them away from the platen. roll shaft 6 is connected a'rear pinion 14;, the connection including a short flexible shaft 15 connected by a universal joint 16 to the main shaft and by a universal joint 17 to the.

pinion. .The forward pressure roll shaft 8 is similarly connected by a flexible shaft 18 to a pinion 19. Both pinions are in mesh with an idle gear 20, which is loose upon the platen axle 3, so that when one roll turns the other must turn with it, lVhere the pitch diameter of the idle gear is equal to that of the platen the diameter of each of the rear and forward rolls should be a trifle greater than the pitch diameter of its pinion, as

illustrated diagrammatically at Fig. t, for

To the rear pressure the purpose above specified... A friction washer ,2 1 is provided between the platen and saio idle gear 20, to enable the platento tend to turn the gear, as above explained.

Said washer has a hub 24, which is fixed by a screw 25 upon the hub 23, of the platen head 22. Said screw is threaded through the hub, 24:, and bears upon a floor 25 0f a recess 25" formed in the hub 23; said floor hemg inclined inwardly-from the outer end to the inner end of the hub. 23, to enable the tightening of the screw 25 to cam the hub 24;

toward the head 22 of the platen, thereby 'gompleting the pressure or tension of the spring washer 21. By loosening'the screw the tension will be relieved. Thus the power of the platen to rotate the pressurerolls 5,

may be regulated. It will be found that a thick card or a thick pack of sheets may be introduced readily between the platen and the rear pressure roll 5, usually without the necessity of first depressing the release key 11, and that the rear pressure roll, being in active rotation'by reason of its connection to the platen driven front roll 7, will cooperate with the platen to bite the leading edge of the card or pack and draw it through; this operation being aided by the frictional connection between the platen and the tram ofv gearing. Upon continued rotation of the platen, the

rear roll effectively cooperates with the to advance the sheet to the front roll laten, latter-through the and derive and the from its connection to the rear roll, and from i the frictional driving connection between the.

platen and the gearing, cooperates with the platen to grasp the leading edge of the card or pack, so that vanced, without liability of skewing or draging.

After the card or pack passes the rear roll,

the latter is accurately adthe latter does not go out of commission, but

being still rotated by the platen, acts a through the gearing to help drive the front roll, and hence to enable the latter to cooperate effectively with the platen to advance the paper to the printing line.

' The pinions 14 and 19 may be mounted on studs 26 and 27 projecting from the platen frame.

The pinion heads may slide endwise upon the studs, to accommodate the vibrations of the shafts 15 and 1S.

,Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I claim:

1. In a typewriting machine, nation with a revoluble platen, of forward and rear pressure rolls to run thereon, and means independent of the platen to connect said pressure rolls to enable one to rotate the other.

2. In a typewriting machine, the combination with a revoluble platen, of forward and rear pressure rolls to run thereon, and means independent of the platen to connect said pressure rolls to enable either to rotate the other.

3. In a typewriting machine, the combination with a revoluble platen, of forward and rear pressure rolls to run thereon, and a train of gearing connecting said pressure rolls independently of the platen.

4. In a typewriting machine, nation with a revoluble platen, of for-ward and rear pressure rolls to run thereon, and a train of gearing connecting said pressure rolls; said train including an idle gear which is mounted to-turn around the axis of rotation of the platen. 1

5. In a typcwriting machine, the combinatioriwith a revoluble platen, of forward and rear pressure roll to run thereon, and a train of gearing connecting said pressure rolls; said train including an idle gear which is mounted to turn around the axis of rotation of the platen, said idle gear and said platen being relatively revolubler. L

the combithe combi- 6. The combination with a. platen'ha ving an axle upon which it rotates, of forward meshing with said pinions, a frictional conand rear pressure rolls having pinions, and

an idle gear loose on said, platenaxle and. -mesh1ng with said pinions.

- 7. The combination with a platen having an axle upon -WhlCll it rotates, of forward and rear pressure rolls having p nions, and

an idle gear loose on said platen axle and nccti'on being, provided betwecn the platen and said idle gear. f

8. Ina typewriting machine, the combination with a revoluble platen, of forward and rear pressure rolls to run thereon, and

a train of connecting devices, frictionally connected to the platen and extending to the pressure rolls and tending to rotate them.

9. In a typewritmg machine, the combination with a revoluhle platen, of a wheel mounted for rotation about the axisof the platen but revoluble independently of the platen, a frictional connection between the platen and said wheel, forward and rear pressure rolls to run upon the platen, and means for enabling said wheel to rotate said pressure rolls.

10. In a typewriting machine, thecombination with a revoluble platen, of a Wheel mounted for rotation about the axis of the platen but revoluble independently of the platen, a frictional connection between the platen and said wheel, forward and rear pressure rolls to run upon the platen, and means for enabling said wheel to rotate said pressure rolls; the connections being so proportioned between the platen and the pressure rolls that the latter, when in contact with the platen, tend to advance at a greater surface speed than the platen.

11. In a typewriting machine, nation with a revoluble platen, of a gear frictionally connected to the platen, pinions meshing with said gear, and pressure rolls connected to said pinions and running upon theplaten; said platen, gear and pressure rolls being so proportioned that the rolls tend to turn at higher surface speed than the platen, when in contact therewith.

12. In a typewrit-in machine, nation with a revolub e platen and forward the combithe combiandrear pressure rolls to run thereon, of a,

frictionally actuated train of devices extending from the platen to the pressure rolls toaid in rotating the latter. 13. In a typewriting machine, the combination with a revoluble platen and forward and rear' pressure rolls to run'thereon, of a frictionally actuated train of devices extending from the platen to the pressurerolls to aid in rotating the latter, said devices including an idle gear turning around the platen axis, and frictionally connected to the platen, pinions in connection with said idle gear, and connections between the pinions and said/ rolls.

14. In a typcwriting machine, the combination with a rcvoluble .pl'aten and forward and rear pressure rolls to run thereon, of a frictionally actuated train of devices extending from the platen to the pressure rolls to aid in rotating the latter, but incapable of enabling the platento control the rotation of said pressure rolls, said devices including an idle gear turning around the platen axis, and frict ionally connected to the platen, pinions in connection with saidzidle gear, and connections between the pinions and said rolls; the parts being so proportioned that roll to run thereon, and frictional devices to enable the platen to turn the pressure roll.

16. In a typewriting machine, the combi nation with a platen and a pressure roll, of a gear frictionally connected to the platen, and a pinion meshing with said gear and. connected to said roll.

17 In a typew riting machine, the combi nation with a platen'and a pressure roll, of a gear frictionally connected to the platen, and a pinion meshing with said gear and connected to said roll; the parts being proportioned to tend to cause the pressure roll toturn at higher surface speed than the platen when in contact with the latter.

18, in a typewriting machine, the combination with a platen having an axle and a gear loose on said axle, of two pinions meshing with said gear, and pressure rolls connected to said pinions.

19. In a typewriting machine, the combination with a platen and a gear rotatablev independently thereof, of two pinions meshing with said gear, and pressure rolls connected to said pinions, said rolls having flexible connections to the pinions.

20. Ina typewriting machine, the combination with a platen and a gear, of two pinions meshing with said gear, and pressure rolls connected to said pinions, said rolls having flexible connections to the pinions, said gear and platen being relatively revoluble, and a friction device between the gear and platen. i I

21. The combination with a platen and a wheel, of a pressure roll to run upon the platen, and a connection between the pressure roll and the wheel; a frictional device being provided between the platen and the roll, to enable the platen to aid through said wheel in turning said roll.

22. In a typewriting machine, the combination with a revoluble platen and a pressure roll to run thereon, of a frictional connecting device running from the platen to the roll and tending to rotate the latter.

23. In a typewriting machine, the combi nation with a revoluble platen, of a pressure roll to run thereon, and frictionally actuated devices to enable the platen to turn the pre sure reil; said trictionally actuated devices eenvoe constructed to tend to turn the pressure roll at greater surface speed than the platen.

24:- ln a typewriting machine, the combination with a revoluble platen and a pressure roll to run thereon, of a frictional connecting device running from the platen to the roll and tending to rotate the latter at a higher surfac'e speed than the platen.

25. in a typewriting machine, the combination with a revoluble platen and a pressure roll. to run thereon, of a frictional connecting device running from the. platen to theroll and tending to rotate the latter, and means for regulating the transmitting power of said frictional device to rotate the roll.

The combination with a platen and a wheel, of a pressure roll to run upon the platen, and a connection between the pressure roll and the wheel; afrietional device being provided between the platen and the roll, to enable the platen to aid through saidwheel in turning said roll; and adjustable means for regulating the frictional. device to increase or diminish the transmitting power thereof to turn the rolls.

27. In a typewriting machine, the combination with a platen and a gear, of two pinions meshing with said gear, pressure rolls having flexible connections to the pinions, said gear and platen being relatively revoluble, a friction device between the gear and platen, and adjustable means for regu' lating the frictional device to increase or diminish the transmitting power thereof to turn the rolls.

28. In a typewriting machine, the combination with a revoluble platen and forward and rear pressure rolls to run thereon, of a frictionally actuated train of devices extendin from the platen to'the pressure rolls to aid in rotating the latter; said dcvices'vineluding an idle gear frictionally connected to the platen; pinions connected to said idle gear; connections between the pinions and saidrolls; said :Erictionally actuated train including a friction washer; and a screw to regulate the pressure or tension of said washer.

ADOLPHUS S. DENNIS. Witnesses Jean 0. Snrrnnr, l nannronr. 

